Solar clock



FIG. 1 is a perspective view of a solar clock showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a right side elevation view thereof, the left side elevation view, and the rear elevation view being identical thereof;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a solar clock, as shown and described. 